Railway traffic controlling apparatus



c. M. MINES 1,909,057

RAILWAY TRAFFIC CONTROLLING APPARATUS May 16, 1933.

Filed April 23, 1932 Fig. 2a

INVENIOR (Zaaae M. Hines By 6255?, M

[11S ATTORNEY.

Patented May 16, 1933 UNITED STATES PATENT OFFICE CLAUDE M. HINES, OFEDGEWOOD, PENNSYLVANIA, ASSIGNOR TO THE UNION SWITCH 7 & SIGNAL COMPANY,OF SWISSVALE, PENNSYLVANIA, A CORPORATION OF PENN- SYLVANIA RAILWAYTRAFFIC CONTROLLING APPARATUS Application filed April 23,

My invention relates to railway traffic controlling apparatus, andparticularly to apparatus for the protection of a railway switch motoragainst overload.

I will describe two forms of apparatus embodying my invention, and willthen point out the novel features thereof in claims.

Fig. 1 of the accompanying drawing is a diagrammatic view showing oneform of apparatus embodying my invention. Fig. 2 is a diagrammatic viewshowing a modification of a portion of the apparatus illustrated in Fig.1, also embodying my invention.

Similar reference characters refer to similar parts in each of the twoviews.

Referring to Fig. 1 of the drawing, the reference character A designatesa railway switch which is actuated by an electric motor M having anarmature 1 and a field 2. Op eratively connected with the switch is acutout controller D comprising a contact arm 3 and contacts 4 and 5.Contact 34 is closed at all times except when the switch occupies itsextreme reverse position and contact 35 is closed at all times exceptwhen the switch occupies its extreme normal position.

The motor M is controlled by a polarized relay E, which in turn iscontrolled by a pole changer L, which may be incorporated in a switchlover of an interlocking machine.

The reference character R designates an automatic overload circuitbreaker having a tripping core 6 and a holding core 7. Mounted on core 6is a tripping winding 8 which is bridged'by a resistor 9 constructed ofmaterial having a high positive temperature-resistance coeiiicient, suchas nickel wire, for example. Mounted on core 6, in inductive relationwith winding 8, is a second winding 10 which supplies energy to aholding winding 11 on core 7 over a normally closed contact 1819.

Contact 18-19 is controlled by armature 20 of a slow-acting relay F insuch manner that this contact becomes opened after a predetermined timeinterval following energization of relay F and motor M. Armature 12 ofthe circuit breaker is normally held open by rod 13 due to thecompression of spring 14 and the attraction of armature 15.

1932. Serial N0. 607,160.

Contact 1617, which is in the circuit for motor M, therefore, remainsclosed at all times except when armature 12 has become actuated. I

As shown in Fig. 1 of the drawing, the switch A occupies its normalposition and polarized relay E as well as pole changer L also occupy thenormal position, relay F being deenergized.

When the switch is to be moved to the reverse position, pole changer Lwill be reversed, thereby reversing contacts 26 and 27 of relay E. Thecircuit for motor M can now be traced from one terminal B of a source,

winding of relay F, contact 16-17, wire 21,

winding 8 and resistor 9 in parallel, wire 22, front neutral contact 23of relay E, wires 24 and 25, polar contact 26, wire 28, armature 1 ofmot-or M, wire 29, polar contact 27, wire 30, 8

contact 47-3 of controller D, wire 31, and

field 2, to the other terminal C of the source. lVhen the switch A is tobe restored to the normal position from the reverse, pole changer L, andtherefore contacts 26 and 27 of relay E, will be restored to theposition shown in the drawing. The circuit for motor M will now be thesame as previously traced up to and including wire 24, from which itwill continue through wire 32, polar contact 27, wire 29, armature 1 ofmotor M, wire 28, polar contact 26, wire 33, contact 53 of controller D,wire 31, and field 2, to the other terminal C of the source.

During the starting period of motor M, the surge of current will nottrip the breaker because the voltage induced in winding 10 will beeffective in energizing the holding winding 11 to keep the breaker fromtripping. Since the pick-up time of relay F is adjusted to be slightlylonger than the duration of the surge current upon starting of themotor, therefore, winding 8 will not be effective to trip the breakeruntil the initial surge has disappeared. Moreover, winding 8 is sodesigned that it will not trip the breaker with winding 11 on opencircuit unless the motor current increases substantially over the valuerequired in the normal operation of motor M.

Should the movement of switch A become obstructed, the motor currentwill rise, and

winding 8 will trip the circuit breaker, opening contact 1617, becauserelay F having previously opened contact 1819, there will exist no pullon armature 15 to overbalance the pull on armature 12 exerted by winding8. Once contact 1617 opens, it will be latched open mechanically andwill. not reclose until pole changer L is reversed to reverse thepolarity of relay E. The details of the latching and reclosmgarrangement for contact 16-17 are not shown as they form no part of mypresent invention.

In order to permit an immediate reversal of switch A away from anobstruction, the release time of relay F is made very short so that thecircuit for holding winding 11 will be immediately efiective to preventtripping of the breaker upon a reversal of the switch, and in order thatrepeated attempts to move the switch can be made in rapid succession, ifnecessary.

The purpose of resistor 9 is to provide added protection againsttripping of the breaker by minor surges of the motor current aftercontact 18-19 opens, and to make tripping more positive upon sustainedoverload, but it will be apparent that resistor 9 is not essential tothe operativeness of my invention. Also, although I have shown anormally closed contact 1819 in series with winding 11, it will beapparent that a normally open contact connected across winding 11 couldbe used to accomplish a similar result, armature 20 of relay F, in thelatter case, operating to close the contact for shortcircuiting winding11 after a predetermined time interval.

Referring now to Fig. 2, the apparatus shown in this figure is the sameas that shown in Fig. 1 except that relay F is energized from thevoltage drop across winding 8, instead of being connected directly intothe motor circuit. The operation of the apparatus of Fig. 2 is similarto the operation of the apparatus of Fig. 1 and will be clear withoutadded description.

It will be apparent that the apparatus as disclosed is adaptable foreither alternating current or direct current operation, because windings10 and 11 will function on a surge of direct current, as well as onsteady alternating current, during the starting interval.

Although I have herein shown and described only two forms of apparatusembodying my invention, it is understood that various changes andmodifications may be made therein within the scope of the appendedclaims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In combination, an electric motor, an operating circuit for saidmotor, a circuit breaker for controlling the supply of current to saidmotor and having a first and a second core, a first winding 011 saidfirst core included in said operating circuit, means controlled by saidfirst winding for tripping said circuit breaker, a second winding onsaid first core in inductive relation with said first winding, a thirdwinding on said second core connected in series with said second windingthrough a normally closed contact, means controlled by said thirdwinding for preventing said circuit breaker from tripping, and aslow-acting relay included in said operating circuit for at timesopening said contact.

2. In combination, an electric motor, an operating circuit for saidmotor, a circuit breaker for controlling the supply of current to saidmotor, a first winding included in said operating circuit, meanscontrolled by said first winding for tripping said circuit breaker, asecond winding in inductive relation with said first winding, a thirdwinding, means controlled by said third winding for preventing saidcircuit breaker from tripping, an energizing circuit for supplying saidthird winding with current induced in said second winding, and meanscontrolled by current supplied to said motor for at times rendering saidenergizing circuit ineffective.

3. In combination, an electric motor, an

operating circuit for said motor, a circuit breaker for controlling thesupply of current to said motor, a first winding included in saidoperating circuit, means controlled by said first winding for trippingsaid circuit breaker, a second winding in inductive relation with saidfirst winding, a third winding, means controlled by said third windingfor preventing said circuit breaker from tripping, an energizing circuitfor supplying said third winding with current induced in said secondwinding, and a time measuring device energized by current supplied tosaid motor for rendering said energizing circuit ineffective after apredetermined time interval following energization of said device.

4. In combination, an electric motor, an operating circuit for saidmotor, a circuit breaker for controlling the supply of cur rent to saidmotor, a first winding included in said operating circuit, meanscontrolled by said first winding for tripping said circuit breaker, asecond winding in inductive relation with said first winding, othermeans controlled by said second winding for preventing said circuitbreaker from tripping, and means governed by current supplied to saidmotor for at times rendering said other means ineffective.

5. In combination, an electric motor, an operating circuit for saidmotor, a circuit breaker for controlling the supply of current to saidmotor, a first winding included in said operating circuit, meanscontrolled by said first winding for tripping said circuit breaker, asecond winding in inductive rela- CLAUDE M. HINES.

